The present invention relates to a transport device for conveying a product as well as to a method for operating the transport device.
Transport systems for conveying products are, for example, used in conveying applications of packaging machines and are known in different embodiments from the prior art. The German patent publication DE 10 2010 027 925 A1 describes, for example, a transport system in which a movable conveyor cart is moved by means of a linear motor drive device. The conveyor cart is thus designed in an articulated manner in order to be able to pass through smaller curve radii. Situations can, however, arise during the operation in which the conveyor carts yaw about the height axis thereof. In a schematically simplified depiction, FIG. 5 shows how this yaw moment M is stabilized in the prior art. According to FIG. 5, a conventional conveyor cart 106 comprises at least three guiding rollers 107 that are offset to one another. Said guiding rollers 107 roll on a corresponding running rail. The yaw moment M can be stabilized by means of the offset arrangement of the guiding rollers 107. In the arrangement according to the prior art, the three forces F1, F2 and F3 must not align so that the yaw moment M can be absorbed in both directions. As a result, a minimum overall size that is greater than 2 times the diameter of the guiding rollers 107 is necessarily required if an arrangement is desired in a single plane in order to prevent parasitic moments. In addition, the guiding rollers 107 that are arranged offset to one another (on the right side in FIG. 5) cannot execute an ideal rolling motion because the rotational axis thereof does not extend through the center point of the circular path. This leads to a transverse movement of the guiding rollers and thus to a relatively high wear and a premature failure of said rollers. As a result, many particles are unnecessarily abraded which are especially undesirable in the area of food and pharmaceutical products or, respectively, food and pharmaceutical packagings.